Cancer is a disease characterized primarily by an uncontrolled division of abnormal cells derived from a given normal tissue and the invasion of adjacent tissues by these malignant cells. Blood or lymphatic transportation can spread cancer cells to other parts of the body leading to regional lymph nodes and to distant sites (metastasis). Cancer is a complex, multistep process that begins with minor preneoplastic changes, which may under certain conditions progress to neoplasia. There are more than 100 different types of cancer, which can be grouped into broader categories. The main categories include: carcinoma, sarcoma, leukemia, lymphoma and myeloma, and central nervous system cancers. The incidence of cancer continues to climb as the general population ages, as new cancers develop, and as susceptible populations (e.g., people infected with AIDS or excessively exposed to sunlight) grow. A tremendous demand therefore exists for new methods and compositions that can be used to treat patients with cancer.
Hematologic or hematopoietic malignancies are cancers of the blood or bone marrow, including leukemia and lymphoma. Leukemia is a type of cancer of the blood characterized by abnormal accumulation of immature white blood cells. There are four types of leukemia: acute lymphocytic leukemia (ALL), acute myelogenous leukemia (AML), chronic lymphocytic leukemia (CLL), and chronic myelogenous leukemia (CML). Acute leukemia is a rapidly progressing disease that results in the accumulation of immature, functionless cells in the marrow and blood. The marrow often stops producing enough normal red cells, white cells and platelets. On the other hand, chronic leukemia progresses more slowly and allows greater numbers of more mature, functional cells to be made.
Leukemia can affect people at any age. The cause of most cases of leukemia is not known. Extraordinary doses of radiation and certain cancer therapies are possible causes. About 90% of leukemia are diagnosed in adults. ICases of Chronic leukemia account for 4.5 percent more cases than acute leukemia. The most common types of leukemia in adults are acute myelogenous leukemia (AML), with estimated 14,590 new cases in 2013, and chronic lymphocytic leukemia (CLL), with about 15,680 new cases in 2013. Chronic myelogenous leukemia (CML) was estimated to affect about 5,920 persons in 2013 (data from the Leukemia and Lymphoma Society, Facts 2013, August 2013).
The dramatic improvement in blood cancer treatment in the latter part of the 20th century is largely the result of chemotherapy. In addition, there are more than 50 drugs individually used to treat these disorders and a number of potential new therapies are under investigation in clinical trials. While current chemotherapy can result in complete remissions, the long term disease-free survival rate for leukemia, in particular AML, is low. For example, the overall relative survival rate for AML was estimated to be about 59% from 2003 to 2009. Therefore, there is a clear and unmet need for effective therapeutics for treatment of blood cancers, including leukemia.
Primary liver cancer is one of the most common forms of cancer in the world. Hepatocellular carcinoma, also known as malignant hepatoma, is the most common form of primary liver cancer, and develops within the hepatocyte. Hepatocellular carcinoma occurs mostly in men and patients that suffer from cirrhosis. It has been the third leading cause of cancer deaths worldwide (Block T M et al., 2003, Oncogene 22:5093-5107). Many patients with hepatocellular carcinoma remain asymptomatic until the disease is in its advanced stages, resulting in ineffective treatment and poor prognosis; the majority of unresectable hepatocellular carcinoma patients die within one year.
Treatment options for hepatocellular carcinoma have been limited, especially in the case of advanced or recurrent hepatocellular carcinoma. Surgery and radiation therapy are options for early stage liver cancer, but not very effective for advanced or recurrent hepatocellular carcinoma. Systematic chemotherapies have not been particularly effective, and there are a very limited number of drugs available for use. The recently approved kinase inhibitor sorafenib has been shown to be effective in treating hepatocellular carcinoma. However, it can slow or stop advanced liver cancer from progressing for only a few months longer than without treatment.
Phosphoramidate derivative of nucleosides are described in WO2013/177219, WO2006/063149, and WO2005/012327.
New therapies for the treatment or prevention of cancer are needed.